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arXiv · 2610.01575

Digitally enhanced Multi-wavelength Stabilization using a Passive Fiber Frequency Reference

Hilma Karlsson·Vaishali Adya·Robert L. Ward·Chathura P. Bandutunga
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Abstract

High-stability frequency stabilization between lasers is essential for applications such as precision metrology, frequency dissemination, and quantum communications. We demonstrate the use of code-based multiplexing of a passive fiber-based interferometer for frequency stabilization and transfer between lasers separated by 85 GHz in frequency using a single shared passive reference. Out-of-loop characterization places an upper bound of sub-kHz/$\sqrt{\text{Hz}}$ on the transferred frequency noise at Fourier frequencies above 40 mHz, with a differential fractional stability of $7\times10^{-13}$ at 1 second. We also demonstrate continuous laser tunability and characterize the residual length noise coupling. Finally, we provide a framework for scaling the architecture to higher laser counts, offering a pathway to scalable, frequency agile stabilization of multiple light sources without the overhead of an optical frequency comb.

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Hilma Karlsson, Vaishali Adya, Robert L. Ward, Chathura P. Bandutunga. 2026-10-01. Digitally enhanced Multi-wavelength Stabilization using a Passive Fiber Frequency Reference. https://arxiv.org/abs/2610.01575

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